1. Field of the Invention
The present invention relates generally to a knife. More specifically, the present invention relates to a field dressing knife for complete field dressing of small and large game and having special application to the severing of the pelvis and brisket bones of small and large game.
2. Background Art
Soon after a game animal is killed, field dressing is required to inhibit the growth of bacteria, thereby preventing premature spoilage of meat. Field dressing refers to the process of preparing the carcass of a game animal, often at the approximate location the animal was killed, to minimize spoilage and preserve the meat for later consumption. Once all life functions have ceased, the carcass begins to decay. Unchecked bacterial growth of the internal organs (viscera) and body fluids spreads quickly through the carcass causing the meat to be unfit for human consumption in a matter of hours, depending on the ambient temperature. To prevent this, the process of gutting, or evisceration, is performed. Gutting involves removing all viscera inside the abdomen and thorax. Removing viscera prevents bacterial growth in the viscera from spreading to the meat, aids in cooling the meat, and prevents unpleasant visceral body fluids from spreading to the meat. Heat and moisture further increase the spread of bacteria. The process of gutting necessarily includes severing the brisket and pelvis bones of the game animal carcass in order to remove all the viscera contained under these bones and to open these areas up for better air drying and cooling.
Several devices have been used over the years by hunters for field dressing large game, especially for severing of the pelvis and brisket bones. One such tool is a handsaw 100 as illustrated in FIGS. 1 and 2. Handsaws 100 tend to be large and awkward to carry in the field while hunting. They work better on the brisket, where a full pass of the saw blade is possible, than on the pelvis bone. For splitting the pelvis bone, it is natural to attempt to saw from one end to the other as shown in FIG. 1. However, a full pass of the saw blade cannot be made because the area between the pelvis bone and the spine is insufficiently deep. This region also contains both the urethra 110 and colon 120. Sawing the pelvis with vertical strokes, while the carcass is on its back, results in puncturing these waste tubes and contamination of the meat.
Placing the handsaw blade across the exposed pelvis bone, parallel to the spine as shown in FIG. 2 is more difficult. In this position, the saw teeth engage a minimum of six inches of bone in a large animal such as an elk. Additionally, sawing from the back end of the elk places the tip of the handsaw 100 directly in line with both the colon 120 and the urine bladder 210. There is, again, danger of meat contamination.
Saw blades used for field dressing large game tend to be difficult to clean. As well, bone rapidly dulls the saw 100 which is difficult to sharpen, especially in the field. For complete field dressing of large game, when using a handsaw 100 for severing the pelvis and brisket bones, both the handsaw 100 and a knife must be carried while hunting.
Another tool used for splitting the pelvis and brisket bones of large game is a hatchet. A hatchet is heavy for hunters to carry all day. The most convenient way to carry a hatchet is to secure it in a scabbard attached to a belt. The hatchet handle, dangling down below the waist, tends to interfere with tall grass, brush, and trees as the hunter moves through the field or woods. Like the handsaw 100, a hatchet works better on the brisket bone than on the pelvis bone. Caution must be taken when chopping through the pelvis bone because of the proximity of the urethra 110, bladder 210, and colon 120, as mentioned in conjunction with the handsaw 100. Unpleasant results due to using a hatchet for splitting the brisket include jagged and sharp bone splinters left protruding from the split brisket. During the removal of the windpipe and lungs, the hunter's arm, with a knife in hand, must pass through the chopped brisket opening in order to cut tendons. As with the handsaw 100, two tools—a hatchet and a knife—must be carried while hunting in order to fully field dress game including splitting the pelvis and brisket using the hatchet.
Another tool available to hunters for field dressing is a wire saw. Wire saws are compact and light for carrying in the field. However, in use, the end of the wire is difficult to thread under the pelvis bone of a large game carcass to extend out on both ends of the pelvis. A goal is to avoid puncturing the bladder 210 or colon 120. Once threaded, the wire saw ends can be pulled back and forth to cut the pelvis. One drawback of the wire saw is that it kinks with use and becomes unfit for reuse. The wire saw is typically only used for the pelvis bone since the pelvis bone is sufficiently small for the saw to pass completely under it and pulled from the top. The brisket is typically too large for this. The hunter must then carry a knife, wire saw, and another device for splitting the brisket.
Knives with saw blades represent another class of tool used for field dressing. These knives are easy to carry but difficult to use to saw through the pelvis and brisket bones of large game animals. The saw blade included in a knife typically does not have sufficient length to be used horizontally across the pelvis bone. Thus, the saw blade is typically oriented vertically to saw through the pelvis bone from one end to the other, aiming the end of the saw blade toward the spine. Again, the urethra 110 and colon 120 are likely to be punctured and the meat contaminated. Knife saw blades tend to have very pointed teeth that dull rapidly. These teeth are difficult to sharpen. Saw blades included with knives, and particularly those having aggressive saw teeth, are difficult to clean. Bone chips, flesh, and fat lodge in-between the teeth, requiring rubbing and/or brushing for removal. An advantage to the use of a knife saw blade is: only one device needs to be carried while hunting.
Present day hunting knives typically have a blade that is too long for the purpose of splitting the pelvis or brisket bones of large game. When impacting such a knife with a stone or stick, as is sometimes done, a misalignment can easily break the knife blade. Additionally, a single-edged blade cannot be effectively worked back and forth in the bone to elongate a groove. As shown in FIG. 3, such an attempt will only elongate the groove 310 in the direction of the sharp edge of the blade 300.
A skinning and gutting knife was disclosed by Bloch in U.S. Pat. No. 5,033,987. The longitudinal axis of the handle of this knife is not parallel with the longitudinal axis of the blade. The disclosed method for applying a large impact force is to strike the back of the blade (opposite the edge) with a foreign object encountered in the field, such as a rock or piece of wood. Such application has the potential to damage a knife by applying a force that is not parallel to the plane of the blade. Furthermore, there is no guarantee a foreign object such as a rock or piece of wood will be handy to a hunter, especially in conditions of deep snow.
A gutting knife is disclosed in U.S. Pat. No. 6,578,271 by Macek. This knife has two forward extensions with a slot between them. In that slot are saw teeth. A method for severing bone is described as applying the slot to the bone and working the handle up and down to apply the saw teeth to the bone. Because the knife blade extends into the abdominal cavity of the carcass, when applying this knife to the severing of a pelvis bone of a large game animal, the probability of cutting or tearing the urethra 110 or the colon 120 is very high. Bone severed by impact of the knife is not disclosed.
There is, therefore a need for a single tool by which small and large game may be field dressed, including the expedient and safe severing of the pelvis and brisket bones.